Electro-Luminescence Display Device and Driving Apparatus Thereof

1. An electro-luminescence display, comprising: a plurality of drive voltage supply lines; a plurality of compensation voltage supply lines; EL cells at each crossing of a plurality of data lines and a plurality of gate lines in a matrix, wherein the EL cells emit light in response to currents applied from the drive voltage supply lines; driving thin film transistors (TFTs) connected between the EL cells and compensation voltage supply lines that control the current applied to the EL cells; and a bias switch, connected between a N−1th compensation voltage supply line of the plurality of compensation voltage supply lines and a control terminal of a Nth driving TFT connected to a Nth compensation voltage supply line of the plurality of compensation voltage supply lines to apply a negative bias voltage to the Nth driving TFT connected to the Nth compensation voltage supply line, thereby compensating for a change of threshold voltage of the Nth driving TFT when a scan pulse is supplied to a N−1th gate line of the plurality of gate lines, wherein the bias switch is controlled by the scan pulse supplied to the N−1th gate line, and wherein the bias switch includes: a control terminal connected to the N−1th gate line; a first input terminal connected to the N−1th compensation voltage supply line; and a second input terminal connected to the control terminal of the Nth driving TFT that is connected to the Nth compensation voltage supply line.

2. The EL display of claim 1 , further comprising: a switching thin film transistor, connected to the gate line, the data line and the control terminal of the driving TFT; and a storage capacitor connected between the compensation voltage supply line and the control terminal of the driving TFT.

3. The EL display of claim 2 , further comprising: a compensation voltage generator that generates a compensation voltage with a high state; and a shift register that sequentially shifts the compensation voltage with a high state to supply the compensation voltage to the plurality of compensation voltage supply lines.

4. The EL display of claim 3 , wherein when the scan pulse is supplied to the N−1th gate line, the compensation voltage with a high state from the shift register is supplied to the Nth compensation voltage supply line and the compensation voltage with a low state from the shift register is supplied to the N−1th compensation voltage supply line.

5. The EL display of claim 4 , wherein when the scan pulse is supplied to the N−1th gate line, the control terminal of the driving TFT is supplied with data via the switching TFT and the second input terminal is supplied with a compensation voltage with a low state from the N−1th compensation voltage supply line.

6. The EL display of claim 4 , wherein when the scan pulse is supplied to the N−1th gate line, the bias switch supplies a compensation voltage with low state from the N−1th compensation voltage supply line to the control terminal of the driving TFT connected to the Nth compensation voltage supply line and a compensation voltage of high state is supplied from the Nth compensation voltage supply line to the second input terminal of the driving TFT.